Carburetor



July 30,' 1929. H. E. MEDLEY CARBURETOR Filed July 9, 1923 2 Sheets-Shet INVENTOR.

TTORNETJ Patented July 30, 1929.

UNITED STATES HERBERT E. MEDLEY, OF VALLEJO, CALIFORNIA.

GARBUBETOR.

Application led .Tuly 9, 1923. Serial No. 650,376.

The present invention relates to improvements in carburetors for internal combustionengines andits particular object is to provide a carburetor in which air is mixed into the fuel before the same is ldrawn by the suction of the engine through a nozzle commonly provided for that purpose. A further object of the invention is to provide means for controlling the amount of air mixed into the fuel before the latter passes through the nozzle whereby simultaneously the amount of fuel passing through the nozzle is controlled.

A further object of the invention is to provide means for pre-heating the air admitted into the fuel. A further obj ect of the invention is to provide a carburetor in which a plurality of nozzles are provided for admitting fuel into a mixing chamber in combination with means for successively rendering the nozzle active as the draft in the mixing chamber increases so that at low speed only one nozzle is drawn on while at high speed a plurality of nozzles are drawn on. Further objects and advantages of my device will ap-v pear as the specification proceeds.

The preferred form of my invention 1s illustrated in the accompanying drawing 1n which Figure 1 shows a vertical section through my carburetor, Figure 2 a top plan view with a certain portion shown in section, Figure 3 a side elevation of my carburetor in connection with the pre-heating system, Figure 4 a detail view showing a valve control for the pre-heating system, Figure 5 a detail view of a choke tube used in my carburetor and Figure 6 a sectional detail view of a float valve used in connection with the same. While I have shown only the preferred form of my invention I wish it to be understood 4.0 that various changes and modifications may be made wit-hin the scope of the claim hereto attached without departing from the spirit of the invention.

My carburetor comprises as its principal parts the fuel reservoir (1) and the mixing chamber (2). The fuel reservoir is constructed in the customary manner and comprises a receptacle (3) allowing gasoline to pass thereinto through an aperture (4) controlled by a needle valve (6) which latter is actuated by means of a float (7) whereby the fuel in the reservoir may be held at a certain level. Before entering the reservoir the gasoline or other fuel used passes through a screen (8).

The mixing chamber is disposed in adjacent relation to the reservoir and is provided at the bottom with a transverse passage (9) communicating at one end through a port (11) with a passage (12) communicating with the reservoir. The area of the port (11) is controlled by means of a needle valve (13) which latter is threaded into the embossment (14) and may be turned by means of a handle (16) This handle is preferably arranged like the handle of a vice, being Vslidable and provided with a head (17) at either end which allows the handle to be projected from the valve stem in either direction for the convenience of the operator.

At the other end the passage (9) is closed by means of the externally threaded flange (18) of a tube (19) which latter extends into the passage in concentric relation to the same so as to leave an annular space around the tube (19). An elbow (21) is threaded into an embossment (22) and bears on a washer (23) interposed between the elbow and the flange (18) of the tube (19). The free end of the elbow connects with the tube (24) as shown at (26) which latter tube connects with the heating element (27) secured to the exhaust manifold of the engine by means of two clamp sections (29) bolted together as shown at (31). The heating element which is shown in detail in Figure 4 comprises a shoe fitting on the exhaust pipe and provided with a longitudinal passage (32) communicating with the tube (24) and a valve controlling its port area. The valve is operated by the lever (34) the free end of which is connected to the rod (36) which latter leads to the dash board to witl in convenient proximity of the driver. The heating element is positioned 'so that the forward open end of its passage 32 is directed toward the front of the engine and at the extreme end the passage (32) flares as shown at (37) to allow more air to be forced through the same through the forward movement of the vehicle and its cooling fan (not shown). The tube (19) extending into the gasoline passage 9 is provided with a plurality of perforations (38) in its top so that while the engine is standing idle gasoline may freely enter the tube (19) and rise in the elbow (21) to the level maintained in the reservoir. From the passage (9) rise three nozzles (41), (42) and (43), one being centrally arranged in the mixing chamber (2) and the other two being disposed on opposite sides of the central nozzle. A choke tube (44) having a flange (46) extending into the mixing chamber in concentric relation to the same is supported on a ledge (47) while being held in place by the member (48) in which is mounted the throttle (49). The choke tube which is cylindrical in its upper portion and narrows down conically toward the bottom is arranged to surroundthecenter nozzle (42). The two other nozzles (41) and (43) are on t-lie outside of the choke tube and communicate with the annular space around the choke tube which latter space is normally' closed by the floating sleeve (51) resting on the seat (52) formed in the inner wall of the mixing chamber (2). rlhis floating sleeve in its resting` position. covers pei'- forations (53) in the lower cylindrical part of the choke tube. But the sleeve may be acted on by the suction of the engine through perforations (54) in the flange (46) and when this suction becomes strong enough it will raise the sleeve (51) to successively uncover, according to the strength of the suctionv the perforations (53) which are arranged in several circumferential rows with the perforations of the upper iow beinglarger than those of the second row7 and those of the second row larger than those of the third row. As will be seen from the drawing the floating sleeve (51) is of substantial proportions and of comparatively heavy weight whereby its motion is rendered smooth and even. It will be noted that when the suction of the engine increasessuliiciently to raise the floating sleeve (51) above the perforations (53), the nozzles (41) and will be drawn on by the suction of the engine and will-mix with the spray from the central nozzle so as to increase its volume. It'should also be noted that the spray from the two nozzles (42) and ('43) being drawn angularly into the mixing chamber through the holes 53 strikes the spray from the central nozzle laterally which produces a boinbarding action serving to further break up the fuel.

`At the bottom the mixing chamber con- Ythreevnozzles and the elbow (21) fill with gasoline to the level maintained in the reservoir (1).v When the engine is started the central nozzle is drawn on and pure gasoline is furnished for the starting operation. As the suction increases the elbow (21) and the inner tubeV (19) begin to empty and to draw on the atmosphere through the tube and the passage in the heating element (2?) so that now air which is pre-heated as soon as the engine warms up is mixed with the gasoline before the latter passes through the nozzle (42). lt will be readily seen that the control of the port area within the heating element allows the operator to simultaneously control the amount of fuel allowed to enter the nozzle since the larger the port area through which air is allowed to enter the less fuel will enter the nozzle and vice versa the less air is allowed the more fuel will enter. `While running at low speed the suction'of the engine is not sucient to raise the floating sleeve (51) so that the central nozzle only is drawn upon by the air passing through the pipe (56) and the mixing chamber into the cylinder intake not shown in the drawing. iis the speed of the engine increases the suction increases simultaneously and lifts the sleeve (51) which latter then floats in tie space between the wall of the mixing chamber and that of the choke tube and uncovers some or all of thel perforations (58). is soon as any of these perforations are uncovered the suction of the engine is allowed to draw on the two outer nozzles (41) and (43) and the spray emanating from these two nozzles strikes the spray emanating'froin the central nozzle at an angle thereby not only increasing the volume of fuel but also serving to further atomize the same. The upper face of the floating sleeve is preferably dislied as shown at (58) so that the whole upper face remains sub-` ject to the draft of` the engine even in its uppermost position.

l claim: n

ln a carburetor, a fuel passageway, nieans for supplying fuel to said passageway, an air 'p ipe disposed in said passageway and being immersed in the fuel for discharging air thereinto, nozzles extending from said passageway and a mixing chamber surrounding said nozzles7 a suction controlled valve closing` certain of said nozzles, said valve being raised by suction for opening all of said nozzles.

HERBERT' E. MEDLEY. 

